* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}
body {
  display: flex;
  flex-direction: column;
  justify-content: flex-start;
  align-items: center;
}
.outer {
  display: flex;
  flex-direction: row;
  justify-content: center;
}
.box {
  width: 800px;
  height: 1200px;
  border: 2px solid hotpink;
  margin-top: 20px;
  background-repeat: no-repeat;
}
.box1 {
  background-image: url(./image/巴黎奥运会_乒乓球_540.jpg);
  /* 设置一个参数，另一个参数等比例改变 */
  /* background-size: 800px;
  background-size: 30%;
  background-size: cover; */
  background-size: contain;
}
.box2 {
  background-image: url(./image/巴黎奥运会_一网无前.jpg);
  /* background-size: cover; */
  background-size: contain;
}
